"Your strike is too shallow!" Kohaku shouted as she easily dodged and blocked both the brothers' attacks. "One of us must win the Grand Bout so that we can give Ruri-nee the cure-all medicine!"

Meanwhile, the rest of you were watching the trio practise from the science when Senku spoke up with a small smirk. "All right, so while Gen's out deceiving Tsukasa, let's get started on that cure-all drug."

"Yeah!" Both you and Chrome yelled in unison, wide grins filled with determination spreading across your faces.

"What are we making with science next?" The brunette questioned as he turned to the green-haired scientist, brown eyes sparkling with eagerness.

The corners of Senku's lips turned into a small, serious frown and said, "There's a material that's just as important for building a civilization as iron. The first man-made material in history, synthesized using science...Glass."

"What's that?" A confused Chrome asked, "Aren't we gonna make all sorts of drugs now that we have electricity and all that?"

"Yeah, we are," Senku answered, but provided no further explanation.

Furrowing your brows, you mused over your friend's words, (e/c) orbs lighting up with understanding. "If we're making the cure-all drugs, we'll be dealing with chemicals and when it comes to that, glass is the best material for that."

"Well said, my lab assistant." Senku grinned as he lifted a hand, ruffling the top of your head with a small, fond smile.

Two pink spots appeared on your cheeks as you beamed at the scientist's praise. Senku let out an amused chuckle at your reaction before facing Chrome to explain. As (Name) pointed out, clay pots are no longer going to cut it for our happy chemistry experiments if we want to make the cure-all sulfa drug. Glass can stand up to just about any chemical. Glass is the foundation of chemistry. Ten billion percent easy to process! Yet it's tough as hell and durable! You can even see through it, which means you can observe the chemicals inside."

"Really? Oh, man." Chrome breathed out in awe, hooked by what Senku had just said.

The corners of his lips stretched into a wide smirk as he turned to look at Suika, who had been quiet all this time and continued, "To top it all off, once we have glass, we might finally get a chance to yank that headpiece off of Great Detective Suika and see her true face."

Before anyone could say or do anything, Senku reached over and pulled the watermelon mask off the young girl, startling both you and Chrome.

"Wait, Senku!" Kohaku, with her keen vision of 11.0, saw everything from where she was still training with the brothers and immediately rushed over to the group, snatching the mask away from the scientist. "Suika doesn't want her face to be seen!"

Senku simply let out a grin and said, "Take a good look."

The three of you glanced down at Suika and were surprised by the innocent appearance with big, sparkling brown eyes and a cute bowl haircut that greeted all of you.

"Wow, Suika! You're perfectly adorable!" Kohaku gushed with heart-filled eyes, completely enthralled by the younger blonde's overall cute look.

At that moment, when Suika's head turned in everyone's direction, her face scrunched up and the innocent expression was replaced with one of like an old person; causing both Kohaku's and Chrome's eyes to bulge in horrified shock.

"What the hell?!" Both of them exclaimed in unison, taken aback by the sudden change.

Meanwhile, you sucked in your breath when realization dawned upon you. Turning to Senku, you whispered, "Senku, do you think that Suika...?"

Said scientist nodded his head but before he could say anything, Suika spoke up. "I have the fuzzy sickness in my eyes. Everything looks fuzzy to me, so I end up looking like this when I try really hard to see, and it's embarrassing."

Then, she popped back on her watermelon mask and all sadness was gone as she happily continued, "But with this mask, for some reason, it's a little easier to see!"

"Yeah, that's the pinhole effect." Senku replied, causing the young girl to glance up at him while he explained, "If you look through an object through a small hole, the light passing through it narrows, bringing it into focus."

"What does glass have to do with Suika's fuzzy sickness?" Chrome asked, scratching the back of his head in confusion.

"It has ten billion percent to do with it!" Senku exclaimed, startling the brunette.

Bending down to Suika's height, you placed both hands on her shoulders and gave her an encouraging smile. "Listen up, Suika. You're nearsighted as hell. That's not a disease. It's not even a defect. Isn't that right, Senku?"

You glanced up at the scientist who nodded his head in agreement and replied in a serious tone. "(Name)'s right. In a technological civilization, it doesn't even bother anyone. We have eyes of science, made from glass. They're called glasses, and they solve everything."

"Science users can make eyes?" Suika whispered, hope began to fill her as she tightened her hands into fists. "That's amazing."

"Yeah," Senku agreed.

"If I could, I'd love to see the beauty of the world, too. Even if it's just once." The young blonde replied with tears streaming down her face beneath her watermelon. "I want to meet you guys without the fuzziness. I want to meet the real you, just once."

The wistfulness in her voice tugged at your heartstrings and you couldn't help but pulled Suika into your arms, tucking her head beneath your chin as you whispered fiercely into her ear. "You will, Suika, you will. When that happens, I promise I'll show you everything that the world has to offer."

You weren't the only one who was moved by the watermelon girl's speech as Chrome declared, "All right. Let's make this glass stuff!"

"Yeah," Kohaku clenched her hands in agreement, turning to Senku. "What do we need to gather, Senku?"

With that, Operation: Clear World had started.

***

"Glass is made mostly from quartz sand," Senku explained while the five of you trekked through the forest. "I didn't see any in the Chrome Collection, actually."

"I'm not going to collect sand." Said brunette grumbled, irked by the scientist's words.

Grinning at the teen's annoyance, Senku continued, "I did see a hint that'll lead us to quartz sand, though."

Chrome glanced back at the green-haired teen with a quizzed look but said nothing as he continued to lead everyone up the mountain. Not long after, all of you arrived at the top where a large cliff stood.

"This was the place. This is where I found this translucent rock as a kid," The brown-haired teen declared as he glanced up at the cliff while holding said rock.

"That little tidbit is worth a ton." Senku began as he broke away from the group, grabbed the stone pickaxe from the basket slung over his body and started to chip away at a random spot on the ground while everyone else watched with curious gazes. "That translucent rock, that crystal, tends to be found in areas of decayed granite, like this place."

Once the top layer of the ground was gone to reveal grey sands, the scientist grabbed a handful of it and said, "And all this sand here is the raw material for glass: quartz sand."

The rest of you let out sounds of excitement and without being told, all of you got to work straight away.

"Yo, the white grains are falling out like crazy!" Chrome exclaimed with a big grin while picking away at the ground.

Next to him, Suika commented. "This is fun!"

"We'll get loads here," Kohaku said as she picked away at a steady speed.

"All this rate, we should be able to gather enough to make glass." You piped up, brows furrowing in concentration.

"Try to gather the see-through ones." Senku instructed and the four of you let out a chorus "Yes, sir!"

Just like this, the rest of the afternoon was spent collecting the quartz sand needed to make glass.

Time skipped

The sun was starting to set by the time all five of you returned to the science shed – baskets filled with quartz sand to the brim – and got started on the next step.

"We grind down all the quartz sand into fine grains," Senku explained and Kohaku did as told, gently rolling a cylindrical stone over said sand.

Once that was done, all the sands were gathered into a large clay pot and brought over to the furnace where Senku did the next step. "Then we mix it with a bunch of other stuff and melt it in the stove."

"What else do we need?" Chrome asked as he watched the scientist.

"We already have everything we need." Senku simply answered. "Thanks to all of our efforts so far. Ten percent calcium carbonate, or sea shells. Twenty percent cooked seaweed. We used all this stuff when we made soap."

Time skipped

"Now..." Senku paused to catch his breath, feeling exhausted after spending another sleepless night in the name of science while Suika fanned him with a leave.

"We just need to throw in some lead," When he was no longer on the verge of death, Senku grabbed the pot filled with melted lead and poured it into a circular mould for the hot liquid to cool down before revealing the finished product. "And we have super see-through lens glass."

Chrome exclaimed in awe, staring at the object in the scientist's hand with wide eyes; both Suika and Kohaku mirroring his expression.

"It's shiny and see-through, like ice!" Suika commented while Kohaku added, "It's like a gem."

Seeing their reactions, you couldn't help but let out a small smile; this feeling never getting old.

Next, Senku led the group over to a small table where on top of it sat a large bamboo held by two wooden x-sticks with a long string coiled around it.

"That's a weird-looking tool." Suika was quick to point out.

Chuckling at her comment, the green-haired teen explained. "We'd die if we tried to polish glass by hand."

Upon hearing that, Chrome made his way over to the science shed, stopping mid-way in his climb up the ladder to glanced over his shoulder at Senku with an excited smile. "We can use that super tough corundum for polishing."

The green-haired scientist replied with a grin. "Glass has a Mohs hardness of about 6. Corundum's is 9."

"Polishing will be a piece of cake!" The brunette gave a thumbs up.

"And the strongest is diamond, with a hardness of 10." Senku continued with his lecture on rocks and their levels of hardness while Chrome's eyes lit up with excitement, hanging onto every word.

"Diamond is nuts! That's insane!"

"Here they go again with their stone talk," Kohaku said in a blunt tone as she stared at the other two with an unimpressed look on her face. "I can't keep up with them."

You simply let out an amused giggle, never finding a day in this new world a dull moment.

***

As Kohaku continued to train and prepare the brothers for the Grand Bout, the rest of you were working on the glass lens for Suika. After a few rounds of eye test, the lens was ready for use as Senku popped them into the eyeholes of the watermelon mask.

"It's done," The scientist announced as he picked up the mask and handed it over to Suika. "Why don't you give it a try, Suika?"

However, just as the young girl was going to accept her watermelon mask, you stepped in; causing both of them to turn you – Senku with a raised brow and Suika with a confused frown.

Smiling, you bend down to the blonde's height and place a hand on top of her head, stroking her hair as you looked into those round, hopeful brown eyes staring up at you. "Suika, remember how I say that I'll show you everything that the world has to offer?"

Said girl nodded her head and the grin on your face widened as you continued, "Well, I thought for your first time, we should make the moment special and memorable? What do you say?"

Suika hesitated for a second before nodding her head. At her agreement, you beamed and stretched a hand out towards her. "I know just the perfect place."

The blonde placed her smaller palm into yours and for the first time since you had known her, you felt her age and realized how young she was. (E/C) eyes softened with fondness, your gaze never leaving hers as you curled your fingers over hers and squeezed tightly, never letting go.

"Let's go," You said as you pulled her towards the direction of the location that you had in mind, followed by Chrome and Senku who was still holding the mask. "I just know the right place for this."

Time skipped

After walking for a bit, you finally arrived at the place. Coming to a halt, you glanced down at Suika and asked in a soft voice, "Suika, can you see what's in front of you?"

"They're just sunflowers," The young girl replied as she squinted her eyes to get a better look. "It's not like I can't see at all, you know."

Without a single word, you took the watermelon mask from Senku and placed it over the blonde's head before taking a step back to give her some space.

Brown eyes widened as the sunflower came to life in front of her, the blurriness that she had always known disappearing as clarity filled her vision. Meanwhile, the smile on your face grew larger as you watched Suika take a few steps ahead and turned to lift her head towards the three of you.

At the clear sight of her friends, tears began to fill Suika's eyes. Overwhelmed, she turned her gaze back towards the field of sunflowers and at that moment, for the very first time in her entire life, she saw the world for what it was; thanks to the power of science.

The four of you, together with Suika's pet dog, decided to stay at the sunflower field and enjoyed the peaceful moment till the sun was sitting low on the horizon, painting the sky in a blend of orange, pink and purple.

"You're all surprisingly good-looking, Senku, Chrome and (Name)." Suika happily commented.

"What do you mean, 'surprisingly'? Jeez." The brunette sweatdropped at the young girl's blunt remark while you giggled, your cheeks dusted a light pink in shyness at the compliment.

Then, out of nowhere, Senku let out a chuckle and all heads turned towards him with surprised looks on your faces.

"Next, we're finally making glass instruments." The green-haired scientist exclaimed; his cheeks flushed with exhilaration as the corners of his lips curled into a sinister smirk. "Now that Suika's labor potential has leveled up super high, we're going to put together a full chemistry set."

"Don't call her 'labor potential'!" Chrome yelled. "Just let it end as a feel-good story!"

Both you and Suika exchanged glances with each other and couldn't help but laughed, causing the brown-haired teen to whip his head towards the two of you while demanding, "What are the two of you laughing about?!"

What a great way to end this moment and you wouldn't have wanted it any other way.

***

"It's time for our fun glasswork class!" Senku declared, grinning like a madman.

"Let's get working!" Chrome exclaimed as he poured a jar of black stones into a large pot sitting over a large fire while the scientist kept stirring the contents with a long stick. "We're throwing these black rocks in, right?"

"I'm going to keep them coming!" Suika declared as she ran over with another jar filled to the brim with said rocks and placed it on the ground next to the other jars.

"You've gotten even more nimble, Suika." You noted, patting the top of the young girl's watermelon mask as she gazed up with an excited grin.

"I don't mess up anymore, now that everything isn't fuzzy." She explained before turning her attention to the large pot when she noticed white bubbles forming over the black rocks. "There's white bubbles coming out."

"This is the foam that's created when you burn obsidian," Senku explained as he picked up a black rock from one of the jars and tossed it into the large pot with the rest of its brethren.

"Oh," You let out a sound of understanding. "So that's what these black rocks are. I was wondering what they could be."

Once there was enough foam to the green-haired teen's liking, he directed Chrome to coat a layer of it over one of the furnaces. "We're using the foam as insulation to make a glassblowing furnace. Then we make an iron straw, then we blow up the glass with air, and that's it."

When all those were done, the brunette did as Senku instructed and blew into the iron rod. However, it wasn't as easy as it sounded. No matter how many times Chrome or Senku tried, each attempt was a failure with the glass coming out all lumpy and weirdly shaped.

Senku let out an exasperated sigh, his lips curled into a wry grin. "Hey, it was our first try. When I first started making clay pots, it took months before they looked decent."

"Months?!" Chrome yelled in disbelief. "We don't have that much time!"

"Chrome has a point," You added, a small frown on your face.

"I'm worried about Ruri-nee's health, too," Kohaku murmured; a worried expression painted across her face.

"I'm not a glass craftsman," Senku replied with a small shrug. "Trial and error is all we've got."

"A craftsman?" Chrome mumbled as a thought crossed his mind.

Then, without so much as an explanation, the brunette turned on his heels and headed towards the direction of the village. Both you and Senku exchanged raised brows, confused and curious by the other's action but said nothing and instead, chose to follow after him with the knowledge that an answer would be given in due time.

All of you, except for Chrome, was waiting by the entrance of the main bridge leading into the village when the sound of footsteps could be heard. All heads turned towards the sound and in the distance, you could see the brown-haired teen returning with an old man bound in ropes.

"Hey, cut it out, Chrome!" The old man pleaded but his words fell on deaf ears as said person continued to drag the poor fellow by the ropes towards where the group was waiting.

'Who the hell is that old man?' You thought to yourself, raising a brow at the peculiar sight.

Once both of them reached the group, Chrome let go of the rope and clasped his hands together, begging the old man. "Come on, Old Man Kaseki! We could really use your skills!"

"Is this how you ask for favors? By tying them up for your kinky rope play?" The old man, now known as Kaseki, demanded angrily. "I'm not lending a single hand to your shady sorcery!"

Chrome let out a hopeless sigh, saying, "See? He just won't come and help us."

"Well, that doesn't mean you should tie him up." You scolded the brunette before turning to the old man with a small bow and apologized. "I'm really sorry on behalf of Chrome. You don't deserve to be treated like this."

Kaseki let out an irritated scoff, but his glare softened slightly at your apology.

"Grandpa Kaseki..." Suika spoke up, drawing everyone's attention to the young girl as she walked up to said old man with a small clay jar held in both hands. "I forget to return your lacquer."

"Oh, that's right," Kaseki replied.

After hearing that, Senku gestured to the shield attached to Kohaku's back and asked, "Old man, were you the one who made that fantastic, season shield? With no iron tools and hardly any dyes to speak of?"

The old man nodded his head. "It was a gift from